Dairy cows in modern production systems are at risk to develop metabolic disorders during the transition period. Reasons for individual differences in susceptibility, as well as the underlying pathomechanisms, are still only partially understood. The development of metaphylactic treatment protocols is needed. In this context, an on-farm prospective 3-fold blinded randomized study involving 80 German Holstein cows was performed throughout 1 yr. The trial involved a thorough recording of the production and clinical traits, clinical chemistry, and liver biopsies and blood and urine sampling at d 14 (mean: 12 d, range: 1-26 d) antepartum (AP), and d 7 (7, 4-13) and 28 (28, 23-34) postpartum (PP) for metabolomics analyses. Two groups received a treatment with butaphosphan and cyanocobalamin (BCC) at either the dosage recommended by the manufacturer or the double dosage (5 or 10 mL/100 kg of body weight 10% butaphosphan and 0.005% cyanocobalamin (Catosal, Bayer Animal Health), n = 20 in each group, parity: 4.2 ± 2.0 and 3.4 ± 1.3, respectively (mean ± SD)] and one group a placebo treatment (NaCl 0.9%, n = 40, parity: 4.0 ± 1.9). The animals were treated at 6 time points (7, 6, and 5 d AP, and 1, 2, and 3 d PP) via intravenous injection. Mass spectroscopy-based targeted metabolomics analysis of blood plasma and liver samples were performed using the AbsoluteIDQ p180 kit (Biocrates Life Sciences), whereas the urine samples were analyzed by nuclear magnetic resonance

The aims of this study were to evaluate histopathologic changes during the transition period, describe the histopathological features of the metabotypes identified in Part I (Schären et al., 2021b), and investigate effects of a metaphylactic treatment with butaphosphan and cyanocobalamin (BCC) on the liver parenchyma.

The liver plays a central role in the postpartum (PP) energy metabolism of the transition dairy cow; however, studies describing the liver metabolome during this period were lacking. The aim of the presented study was therefore to compare the alterations in the liver and blood metabolome of transition dairy cows. For this purpose, an on-farm trial with 80 German Holstein cows (mean lactation number: 3.9; range: 2-9) was performed, with thorough documentation of clinical traits and clinical chemistry, as well as production data. Liver biopsies and blood samples were collected at d 14 (mean: 12 d, range: 1-26 d) antepartum (AP), d 7 (7, 4-13) and 28 (28, 23-34; mean, earliest-latest) PP for targeted mass spectroscopy-based metabolomics analysis using the AbsoluteIDQ p180 kit (Biocrates Life Sciences). Statistical analysis was performed using multivariate (partial least squares discriminant analysis) as well as univariate methods (linear mixed model). Multivariate data analysis of the liver metabolome revealed 3 different metabotypes (A = medium, B = minor, C = large alterations in the liver metabolome profile between AP and PP). In metabotype C, an increase of almost all acylcarnitines, lysophosphatidylcholines (lysoPC), sphingomyelins, and some phosphatidylcholines (PC, mainly at 7 d PP) was observed after calving. In contrast to metabotype C, the clinical data of the metabotype B animals indicated a higher PP lipomobilization and occurrence of transition cow diseases. The liver metabolome profile of these animals most likely mirrors a failure of adaptation to the PP state. This strong occurrence of metabotypes was much less pronounced in the blood metabolome. Additionally, differences in metabolic patterns were observed across the transition period when comparing liver and blood matrices (e.g., in different biogenic amines, acylcarnitines and sphingolipids). In summary, the blood samples at 7 d PP showed lower acylcarnitines and PC, with minor alterations and a heterogeneous pattern in AA, biogenic amines, and sphingomyelins compared with 14 d AP. In contrast to 7 d PP, the blood samples at 28 PP revealed an increase in several AA, lysoPC, PC, and sphingomyelins in comparison to the AP state, irrespective of the metabotype. In the liver biopsies metabotype B differed from metabotype C animals ante partum by following metabolites: higher α aminoadipic acid, lower AA, serotonin, taurine, and symmetric dimethylarginine levels, lower or higher concentrations of certain acylcarnitines

Zusammenfassung Ziel Das vermehrte Auftreten von Ketose in der Transitphase bei Milchkühen verursacht hohe ökonomische Verluste. Die frühzeitige Identifizierung betroffener Tiere bereits im subklinischen Stadium ermöglicht, die Erkrankungshäufigkeit zu reduzieren und Verluste zu vermeiden. Ziel der Studie war, die Eignung eines mobilen Testgeräts zur Analyse der Betahydroxybutyrat-Konzentration (BHB-Konzentration) in der praktischen Anwendung zu prüfen. Darüber hinaus sollten die mit diesem Gerät gemessenen BHB-Konzentrationen mit denen verglichen werden, die mit einer Laborreferenzmethode aus dem Blut der V. jugularis ermittelt wurden. Material und Methoden Bei 81 Milchkühen wurde zu 7 Zeitpunkten (14 und 7 Tage a. p. sowie 7, 14, 21, 28, 42 Tage p. p.) Blut für die Analyse der BHB-Konzentration entnommen. Zur Messung im Labor mit einer kinetisch-enzymatischen Methode diente Blut aus der V. jugularis und V. oder A. coccygea mediana, zur Messung mit dem Gerät WellionVet BELUA Blut aus der V. oder A. coccygea mediana sowie Kapillarblut (gewonnen am Übergang der Haut zur Schleimhaut an der Vulva). Ergebnisse Anfängliche Anwendungsfehler bei der Bedienung des Geräts konnten mit Training abgestellt werden. Bei den Analyseergebnissen im Labor lagen die BHB-Konzentrationen aus dem Blut der V. jugularis um 0,07 mmol/l niedriger als die in Blut aus der V. oder A. coccygea mediana. Die mit dem Testgerät ermittelten BHB-Konzentrationen in Proben der V. oder A. coccygea mediana lagen um 0,13 mmol/l niedriger und die im Kapillarblut um 0,12 mmol/l niedriger als die im Labor aus dem Blut der V. jugularis gemessenen. Die mit dem Testgerät gemessenen BHB-Konzentrationen differierten zwischen den beiden Entnahmelokalisationen nicht signifikant. Schlussfolgerung Für die Kapillarblutentnahme eignet sich die Lokalisation am Übergang von Haut zu Schleimhaut an der Vulva. Das Gerät WellionVet BELUA liefert sofort Ergebnisse mit guter Übereinstimmung zwischen den Messwerten in Proben von verschiedenen Blutentnahmeorten wie auch im Vergleich zur Laboranalyse. Das Testsystem ist zur Anwendung in Milchviehbetrieben geeignet. Als Matrix kann sowohl Kapillarblut als auch Blut aus der V. oder A. coccygea mediana empfohlen werden.

Background Recumbent cows are a diagnostic challenge because of a wide range of differential diagnoses, which include trauma, neurological and metabolic disorders, malnutrition and mineral deficiencies. This case report describes recumbent suckler cows that presented as a herd problem. In addition to weakness due to inanition, Cu and Se deficiencies were considered as possible aetiologies of the recumbency. Furthermore, Trypanosoma (T.) theileri, a blood parasite of unknown importance in Germany, was detected in the blood of some cows. Case presentation Three recumbent cows were referred to the Clinic for Ruminants and Swine, Faculty of Veterinary Medicine of the University of Leipzig. They were unable to rise and had low body condition scores and rough hair coats. Haematological and serum biochemical analyses showed neutrophilia, electrolyte imbalances, increased activities of muscle and liver enzymes and decreased concentrations of trace elements, especially Copper (Cu) and Selenium (Se). T. theileri was detected in a routine blood smear from one cow. The cows did not respond to an intensive care protocol, which included intravenous fluids and electrolytes, mineral substitution, non-steroidal anti-inflammatories and antibiotics, and were therefore euthanized or died. Postmortem examination showed cachexia, subcutaneous and scleral oedema and muscular dystrophy, especially in the hind limbs. Follow-up examination of the herd of origin produced similar findings including the detection of T. theileri in a large proportion of the herd. Ration analysis revealed considerable undersupply of several nutrients. Conclusions Based on all findings, an aetiological diagnosis of trace mineral and nutrient deficiency with possible involvement of T. theileri was made.